I went back to my OnePlus One, as I was itching for some stock type Marshmallow 6.0 goodness, and there are some pretty good CM13 ROM's out now for the OPO.
I haven't used my OnePlus One since the Spring, dusted off the old OPO, flashed the latest firmware, then erased everything, and flashed the best CM13 ROM, got it all setup, and I was like hot damn, Marshmallow is pretty sweat
I took my SIM card out of my Note 5, and popped in the OPO, and ran it all night and this morning.
Long story short; I am back to my Note 5 and happy as a clam
Short story long; I forgot just how poor the OPO display is, holy cow is it bad compared to the Note 5. Seems like light years apart in technology. The OnePlus One looks like the stone age screen, and the Note 5 screen was built by Commander LaForge on the Starship Enterprise.
And the curved back, I forgot how much I HATE phones with curved backs, my Nexus 6 had that curved back too, and God I couldn't stand that terrible design. It rocks back and forth like a canoe in choppy water when laying on a table. I love laying my phone down on the table and using it while eating, and doing some computer work, and with a flat phone like the Note 5 it's just so simple, easy, and smooth to tap away on it while laying down flat.
One thing was the speed difference, or almost lack thereof in a way. I run Nova Launcher on both phones, and have the speed set up exactly the same to " relaxed", and also Developer options the same too, with 1 second animations. While the Note 5 did feel smoother and overall faster, I can't say the OPO was a lagging turtle or slow motion, the speed difference did NOT feel night and day. Where my rooted and ROM'd Note 5 has ZERO lag, the OPO maybe had a hair hiccup lag here or there, but just a little.
Biggest thing, was how the newer stock Android 6.0 Marshmallow compared to Touchwiz running 5.1.1 did not feel or look, or perform all that different from each other. I am running a Material theme on my Note 5, and it looks pretty cool, and I have stated over the years how much I HATE Touchwiz, just loath it, but not sure what happened, the Note 5's TW + a Material theme is really slick, super smooth and fast, and I admit I like the Dialer, and Contacts, and E-mail, Lock screen better on Touchwiz than I do stock Android.